An apparatus is an implant-dentist more readily identifiable visual segregation amongst their oral-surgery arbor-tools used conjunction with a conventional hand-held power/rotary-tool. The arbor-tools generally has at least a tri-echeloned set, wherein are included progressions of drill-bit lengths and companion thread-taps appearing in three different diameters. Additionally, the drill-bit shanks are optionally provided with a radial-flange serving as an automatic depth-stop device and these radial-flanges may include a distinctive annular-marker device serving to readily indicate the length of the selected drill-bit, thereby obviating usual procedure of stopping to confirm via the obscure conventional alpha-numeric indicia.